public QueryStringFilterUserControl(string filterName, string filterDescription) : base(filterName, filterDescription)
 {
     InitializeComponent();
     singleFilterGroup.Text = filterName;
     singleFilterGroup.AccessibleDescription = filterDescription;
     SearchConditionRichTextBox.GotFocus    += SearchConditionRichTextBox_GotFocus;
     SearchConditionRichTextBox.LostFocus   += SearchConditionRichTextBox_LostFocus;
     SearchConditionRichTextBox.LostFocus <RichTextBox>();
     SearchConditionsListBox.EnabledChanged += SearchConditionsListBox_EnabledChanged;
 }
 private void AddSearchConditionButton_Click(object sender, EventArgs e)
 {
     if (!string.IsNullOrEmpty(SearchConditionRichTextBox.Text) && !SearchConditionsListBox.Items.Contains(SearchConditionRichTextBox.Text))
     {
         if (!SearchConditionRichTextBox.Text.Equals(ControlExtensions.DefaultFieldValue))
         {
             SearchConditionsListBox.Items.Add(SearchConditionRichTextBox.Text);
         }
         SearchConditionRichTextBox.Text = string.Empty;
         SearchConditionRichTextBox.LostFocus <RichTextBox>();
     }
 }